BoilerFaultCodesWorcester Bosch P5 Fault Code
The Worcester Bosch P5 fault code means: your boiler is simply running a routine internal check as it starts up and there is no actual fault with the appliance.. It appears on 2 Worcester Bosch models in our database.
Technical description: Part of the self-test sequence sequence when the appliance is switched on.
What causes the Worcester Bosch P5 fault?
This code appears because the boiler is performing a routine electronic check of its internal sensors and components at the moment it is switched on. It is a programmed safety sequence designed to ensure everything is working correctly before the burner fires up. It is not triggered by a mechanical failure or a broken part.
DIY fix possible
Wait for approximately 30 to 60 seconds for the code to disappear naturallyEnsure the power supply to the boiler remains switched on during this processIf the code stays on the screen for several minutes, try pressing the reset button once
Find a Gas Safe engineer
Search the official register for a qualified engineer in your area.
Gas Safe Register →Worcester Bosch models that show the P5 fault code
Click a model for the full fault code list and model-specific repair notes.
Source
Worcester Bosch P5 fault code information on this page is sourced and cross-checked against the official Worcester Bosch service / installation manuals for each affected model.
Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed 27 April 2026